zRogue is an interesting programming exercise and well done, but not really something worthwhile for the player, I believe. Rogue is readily available on many other platforms. Since it is entirely text-based, the novel connection to interactive fiction is somewhat credible, but very little remains to make it interesting for the interactive fiction audience.
If you're an IF programmer and want to be impressed, go ahead and take a look. If you want to play IF, don't bother.
Describing it would ruin it, other than to say that it's surprisingly fun for seemingly almost no reason at all. It should take you only a few minutes, none of which will you regret.
